ASTM-A-49---12

Designation:A49−12StandardSpecificationforHeat-TreatedCarbonSteelJointBars,MicroalloyedJointBars,andForgedCarbonSteelCompromiseJointBars1ThisstandardisissuedunderthefixeddesignationA49;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.ThisstandardhasbeenapprovedforusebyagenciesoftheDepartmentofDefense.1.Scope1.1Thisspecificationcoversheat-treatedcarbonsteeljointbars,microalloyedjointbars,andforgedcompromisejointbarsforgeneraluseinstandardrailroadtrack.1.2Thejointbarsmaybeusedfortheproductionofinsulatedjoints.1.3Thevaluesstatedininch-poundunitsaretoberegardedasthestandard.Thevaluesgiveninparenthesesareforinformationonly.2.ReferencedDocuments2.1ASTMStandards:2A29/A29MSpecificationforSteelBars,CarbonandAlloy,Hot-Wrought,GeneralRequirementsforA370TestMethodsandDefinitionsforMechanicalTestingofSteelProductsA700PracticesforPackaging,Marking,andLoadingMeth-odsforSteelProductsforShipment2.2AmericanRailwayEngineeringandMaintenanceofWayAssociationManualforRailwayEngineering33.OrderingInformation3.1Ordersforjointbarsunderthisspecificationshallincludethefollowinginformationasappropriate:3.1.1Quantity—numberofpairsofbars,3.1.2Type—designortypebaralongwithsectiondesigna-tionandweightofrailsbeingjoined,3.1.3Dimension—overalllength,3.1.4Punching—type(elliptical,oval,round,orcombina-tions),size,number,location,spacingandelevationofpunchedholes,withdimensionaldrawingifnecessary,3.1.5HeadEasement—ifrequired,and3.1.6CertificationandTestReportRequirements(see12.1).4.Manufacture4.1Thesteelshallbemadebyoneorbothofthefollowingprocesses:basic-oxygenorelectric-furnace.4.1.1Thesteelmaybecastbyacontinuousprocess,oriningots.4.2HeatingandQuenching—Quenchedcarbon-steeljointbarsandforgedcompromisejointbarsshallbeuniformlyheatedforpunching,slotting,shaping,andforgingandsubse-quentlyquenched.Maximumdepthofdecarburizedlayerofforgedbarsshallnotexceed0.040in.4.3Microalloyedjointbarsshallbeproducedfromhotrolledsteelsections.Barsshallbeshearedorsawedcold,andholesshallbedrilled.Noreheatingandquenchingisrequired.5.ChemicalRequirements5.1Thechemicalcompositionofthequenchedcarbon-steeljointbarsandforgedcompromisejointbarsdeterminedasprescribedin5.3shallbewithinthelimitsshowninTable1.5.2Thechemicalcompositionofthemicroalloyedjointbarsshallbeagreeduponbythepurchaserandthemanufacturer.Microalloyingshallbeaccomplishedwithcolumbium,vana-dium,andnitrogen,orcombinationsthereof.5.3HeatorCastAnalysis—Separateanalysisshallbemadefromtestsamplesrepresentingoneofthefirstthreeandoneofthelastthreeingotsorcontinuouslycastbloomspreferablytakenduringthepouringoftheheat.Determinationsmaybemadechemicallyorspectrographically.AnyportionoftheheatmeetingthechemicalanalysisrequirementsofTable1maybeapplied.Thefirstheatanalysisshallberecordedastheofficialheatanalysis,butthepurchasershallhaveaccesstoallladleanalyses.Additionally,anymaterialmeetingtheproductanaly-sislimitsshowninTable2maybeappliedaftertestingsuchmaterialinaccordancewithSpecificationA29/A29M.1ThisspecificationisunderthejurisdictionofASTMCommitteeA01onSteel,StainlessSteelandRelatedAlloysandisthedirectresponsibilityofSubcommitteeA01.01onSteelRailsandAccessories.CurrenteditionapprovedMarch1,2012.PublishedApril2012.Originallyapprovedin1915.Lastpreviouseditionapprovedin2006asA49–01(2006).DOI:10.1520/A0049-12.2ForreferencedASTMstandards,visittheASTMwebsite,@astm.org.ForAnnualBookofASTMStandardsvolumeinformation,refertothestandard’sDocumentSummarypageontheASTMwebsite.3AvailablefromAmericanRailwayEngineeringandMaintenanceofWayAssn.,10003DerekwoodLane,Suite210,Lanham,MD20706.Copyright©ASTMInternational,100BarrHarborDrive,POBoxC700,WestConshohocken,PA19428-2959.UnitedStates1CopyrightbyASTMInt'l(allrightsreserved);5.4ProductAnalysis—Whenladletestsarenotavailable,finishedmaterialrepresentingtheheatmaybeproducttested.TheproductanalysisallowancebeyondthelimitsofthespecifiedladleanalysisshallbewithinthelimitsforproductanalysesspecifiedinTable2.5.4.1Ananalysismaybemadebythepurchaserfromasampletakenfromafinishedjointbarrepresentingeachheatorcast.ThechemicalcompositionthusdeterminedshallconformtotherequirementsinTable2.6.TensileRequirements6.1Properties:6.1.1ThematerialasrepresentedbyatensiontestspecimenshallconformtothetensilepropertiesprescribedinTable3.6.1.2TheyieldpointprescribedinTable3maybedeter-minedbythedropofthebeamorhaltofthegageofthetestingmachine,orbyuseofdividers.Whereadefiniteyieldpointisnotexhibited,theyieldstrengthmethoddefinedin6.1.3shallbeused.6.1.3TheyieldstrengthprescribedinTable3shallbedeterminedbyastraingageorextensometerreadingto0.0002in.(0.005mm).Yieldstrengthmaybedefinedasthestressat0.5%totalstrainunderloadorasthestressat0.2%offset.ThemethoddescribedinTestMethodsandDefinitionsA370shallbefollowed.Aftertheyieldpointhasbeenpassed,theextensometermaythenberemovedandthetestconti